A critical need exists to develop tumor-specific non-invasive imaging agents. Currently, most imaging is based on the detection of mass lesions or general metabolic activity. Imaging agents that elucidate the pathobiology of cells in the masses are lacking. Lymphomas are characterized by the clonal malignant expansion of leukocytes and tend to grow in masses. Over-expression of leukocyte-function-associated antigen-1 receptors (LFA-1) on most lymphomas with no expression on non-hematopoetic cells make them amenable targets. An allosteric inhibitor of LFA-1 has been developed, the small molecule alkyl-amino-NorBirt. Determination of its structure activity relationship has permitted modifications allowing radiometal attachment through an alkylamino linker. We postulate that radiolabeled alkyl-amino-NorBirt will retain its binding affinity towards LFA-1 and thus can be used as a non-invasive imaging agent. Our previous work has demonstrated that the radiometal, 213Bi, can be effectively incorporated into the alkyl-amino-NorBirt. We propose to link a radiometal with good imaging characteristics to image LFA-1 overexpression in vivo. The radiolabeled alkyl-amino-NorBirt will allow imaging of lymphoma cells trafficing in the vasculature and tissues, diagnosis and staging, as well as monitoring responses to other therapeutic interventions.